Revert unintentional change

Author: sanych-sun

source/server-discovery-and-monitoring/server-discovery-and-monitoring.md

@@ -897,7 +897,7 @@ else:
         ):
             # Stale primary.
             # The error field MUST include the substring "primary marked stale due to electionId/setVersion mismatch"
-            replace serverDescription with a default ServerDescription of type "Unknown"
+            replace serverDescription with a default ServerDescription of type "Unknown" 
             checkIfHasPrimary()
             return